package com.linjj.seckill.redis;

import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
/**
 *封装redis方法，使其能存取对象
 * */
@Service
public class RedisService {
    @Autowired
    private JedisPool jedisPool;
    public <T> boolean set(KeyPrefix keyPrefix,String key,T value) {
        Jedis jedis = null;
        try{
            jedis = jedisPool.getResource();
            String realKey = keyPrefix.getPrefix()+key;
            String str = beanToString(value);
            if(str==null || str.length()<=0){
                return false;
            }
            int seconds = keyPrefix.expireSeconds();
            if(seconds==0){
                jedis.set(realKey,str);
            }
            else{
                jedis.setex(realKey,seconds,str);
            }
            return true;
        }finally {
            returnToPool(jedis);
        }
    }

    public <T> T get(KeyPrefix keyPrefix,String key,Class<T> clazz) {
        Jedis jedis = null;
        try{
            jedis = jedisPool.getResource();
            String realKey = keyPrefix.getPrefix()+key;
            String str = jedis.get(realKey);
            T t = stringToBean(str,clazz);
            return t;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 判断key是否存在
     * */
    public <T> boolean exists(KeyPrefix prefix, String key) {
        Jedis jedis = null;
        try {
            jedis =  jedisPool.getResource();
            //生成真正的key
            String realKey  = prefix.getPrefix() + key;
            return  jedis.exists(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 增加值
     * */
    public <T> Long incr(KeyPrefix prefix, String key) {
        Jedis jedis = null;
        try {
            jedis =  jedisPool.getResource();
            //生成真正的key
            String realKey  = prefix.getPrefix() + key;
            return  jedis.incr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 减少值
     * */
    public <T> Long decr(KeyPrefix prefix, String key) {
        Jedis jedis = null;
        try {
            jedis =  jedisPool.getResource();
            //生成真正的key
            String realKey  = prefix.getPrefix() + key;
            return  jedis.decr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    public static <T> T stringToBean(String str,Class<T> clazz) {
        if(str==null || str.length()<=0 || clazz==null){
            return null;
        }
        if(clazz==int.class || clazz==Integer.class){
            return (T)Integer.valueOf(str);
        }
        if(clazz==String.class){
            return (T)str;
        }
        if(clazz==long.class || clazz==Long.class){
            return (T) Long.valueOf(str);
        }
        if(clazz==double.class || clazz==Double.class){
            return (T) Double.valueOf(str);
        }
        else{
            return JSON.toJavaObject(JSON.parseObject(str), clazz);
        }
    }
    public static <T> String beanToString(T value){
        if(value==null){
            return null;
        }
        Class<?> clazz = value.getClass();
        if(clazz==int.class || clazz==Integer.class){
            return ""+value;
        }
        if(clazz==String.class){
            return (String) value;
        }
        if(clazz==long.class || clazz==Long.class){
            return ""+value;
        }
        if(clazz==double.class || clazz==Double.class){
            return ""+value;
        }
        else{
            return JSON.toJSONString(value);
        }
    }

    private void returnToPool(Jedis jedis) {
        if(jedis!=null){
            jedis.close();
        }
    }

    public boolean delete(KeyPrefix prefix, String key) {
        Jedis jedis = null;
        try {
            jedis =  jedisPool.getResource();
            //生成真正的key
            String realKey  = prefix.getPrefix() + key;
            long ret =  jedis.del(realKey);
            return ret > 0;
        }finally {
            returnToPool(jedis);
        }
    }
}
